Data center management using device identification over power-line

ABSTRACT

In one embodiment, a first device (e.g., a host device or power distribution unit) stores identification information of the first device, and determines, over a power connection, when the first device is in powered connectivity with a second device (e.g., a power distribution unit or host device, respectively). The first device may then communicate, with the second device over the power connection, identification information of at least one of either the first or second device, where the communicated identification information is accessible to a third device (e.g., a server) via a data network due to the communicating over the power connection. In another embodiment, a server may determine, based on the identification information, a physical location of a power distribution unit, and may deduce, based on the physical location of the power distribution unit, that a host device is physically located at the physical location of the power distribution unit.

TECHNICAL FIELD

The present disclosure relates generally to computer networks, and, moreparticularly, to data center management using device identification overpower-line.

BACKGROUND

Keeping track of physical devices and their location can often be atedious and time-consuming task. This is particularly the case forequipment within a data center. Keeping track can often be a complexprocess involving a large amount of hours spent auditing, bar-coding,and documenting devices as they are commissioned, migrated within afacility, or decommissioned from a facility. As these are oftenperformed as a manual process completed by workers, there is opportunityfor errors in collection of this data, as well as opportunity for datato become out-of-date. In addition, knowledge of and/or control over thepower state of devices in a data center has long been a difficultproblem, with many attempts to address such power state managementleading to either overly complex systems or otherwise inefficientsystems.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments herein may be better understood by referring to thefollowing description in conjunction with the accompanying drawings inwhich like reference numerals indicate identically or functionallysimilar elements, of which:

FIG. 1A illustrates an example networked device and power arrangement(e.g., a rack);

FIG. 1B illustrates another example networked device and powerarrangement;

FIG. 2 illustrates an example device;

FIG. 3 illustrates an example of device identification over power-linefor data center management;

FIGS. 4A-4C illustrate example communications for data center managementusing device identification over power-line;

FIG. 5A illustrates an example simplified procedure for data centermanagement using device identification over power-line, particularlyfrom the perspective of a host device communicating its identificationinformation;

FIG. 5B illustrates an example simplified procedure for data centermanagement using device identification over power-line, particularlyfrom the perspective of either a host device or PDU communicatingreceived identification information;

FIG. 5C illustrates an example simplified procedure for data centermanagement using device identification over power-line, particularlyfrom the perspective of a management device (e.g., server);

FIGS. 6A-6D illustrate examples of data center management using deviceidentification over power-line;

FIG. 7 illustrates an example communication for data center managementusing device identification over power-line;

FIGS. 8A-8C illustrate examples of data center management overpower-line; and

FIG. 9 illustrates an example simplified procedure for data centermanagement using device identification over power-line, particularlyfrom the perspective of a PDU communicating management commands.

DESCRIPTION OF EXAMPLE EMBODIMENTS Overview

According to one or more embodiments of the disclosure, a first device(e.g., a host device or a power distribution unit) stores identificationinformation of the first device, and determines, over a powerconnection, when the first device is in powered connectivity with asecond device (e.g., a power distribution unit or a host device,respectively). The first device may then communicate, with the seconddevice over the power connection in response to the poweredconnectivity, identification information of at least one of either thefirst device or the second device, where the communicated identificationinformation is accessible to a third device (e.g., a server) via a datanetwork due to the communicating over the power connection.

According to one or more additional embodiments of the disclosure, aserver receives identification information of a host device and a powerdistribution unit over a data network, where the host device and powerdistribution unit initially communicated the identification informationover a power connection that provides powered connectivity from thepower distribution unit to the host device. The server may thendetermine, based on the identification information, a physical locationof the power distribution unit, and may deduce, based on the physicallocation of the power distribution unit, that the host device isphysically located at the physical location of the power distributionunit.

DESCRIPTION

As will be understood by those skilled in the art, a data center is afacility that stores computer systems and associated components (e.g.,computational, telecommunications, and storage systems). Often, datacenters use redundant or backup power supplies, in addition to redundantdata communications connections and other systems.

FIG. 1A illustrates an example simplified networked device and powerarrangement, such as a portion of a data center 100, where a supportingrack 110 may be associated with one or more power distribution units(PDUs) 120 (e.g., 120 a and 120 b), which are configured to supply powerover powered connections 125 (e.g., 125 a and 125 b, respectively) toconnected host devices 130 (e.g., 130 a, 130 b, and 130 c), such asrouters, switches, servers, security devices, etc. In addition, thedevices 130 may be connected to a data network 140 a (e.g., an Ethernetnetwork), while PDUs 120 may also be connected to a data network 140 b,which in certain embodiments, may be the same data network as 140 a.FIG. 1B illustrates another example simplified networked device andpower arrangement, illustrating the core components of FIG. 1A in asimplified block diagram view.

As noted above, keeping track of physical devices and their location canoften be a tedious and time-consuming task. This is particularly thecase for equipment within a data center. Keeping track can often be acomplex process involving a large amount of hours spent auditing,bar-coding, and documenting devices as they are commissioned, migratedwithin a facility, or decommissioned from a facility. As these are oftenperformed as a manual process completed by workers, there is opportunityfor errors in collection of this data, as well as opportunity for datato become out-of-date. In addition, knowledge of and/or control over thepower state of devices in a data center has long been a difficultproblem, with many attempts to address such power state managementleading to either overly complex systems or otherwise inefficientsystems.

In addition to the above listed problems of device tracking,occasionally it is necessary to conduct work on a data center's powersupply. Usually this is conducted on the A-side or B-side separately.That is, as most host devices 130 have dual power supplies, if one goesdown the machine will keep operation. However, if a power supply hasfailed, or a chassis has only one power supply, the owner wouldgenerally appreciate being notified that they will be impacted by theoutage. Identification of these hosts is currently conducted manually.Also, where a host has been incorrectly wired such that both powersupplies have been connected to the same power side, the owner should beidentified such that the wiring can be remediated.

The techniques herein present a way for host devices to automaticallyidentify themselves and be added to data center inventories via the useof an internal host identifier communicated with a smart PDU viapower-line communication. In general, PDUs 120 (or “cabinet PDU” (CDU),or other types of smart power units), are often deployed in a knownphysical location. That is, PDUs will often be configured as part of adata center deployment, and are left static during the operational phaseof a data center. Devices 130 will generally be connected to PDUs in therack 110 in which they reside, associating the device 130 to a physicallocation (i.e., of the PDU 120). This will allow rapid inventoryupdating via an automated process as described herein. For instance, asdescribed below, various administrative features become availablethrough the techniques herein, particularly opposed to manually takinginventory, such as querying a smart PDU to identify hardware within arack or determining rack space utilization rapidly and accurately, aswell as querying A-side and B-side smart PDUs in a rack to allow rapidhighlighting of devices with single or failed power supplies during datacenter power maintenance.

Specifically, according to one or more embodiments of the disclosure asdescribed in detail below, a first device (e.g., a host device 130 or aPDU 120) stores its identification information, and determines, over apower connection 125, when it is in powered connectivity with a seconddevice (e.g., a PDU or a host device, respectively). The first devicemay then communicate, with the second device over the power connectionin response to the powered connectivity, identification information ofat least one of either the first device or the second device, where thecommunicated identification information is accessible to a third device(e.g., a server) via a data network 140 due to the communicating overthe power connection.

According to one or more additional embodiments of the disclosure, aserver receives identification information of a host device 130 and aPDU 120 over a data network 140, where the host device and powerdistribution unit initially communicated the identification informationover a power connection that provides powered connectivity from thepower distribution unit to the host device (mentioned above). The servermay then determine, based on the identification information, a physicallocation of the PDU, and may deduce, based on the physical location ofthe PDU, that the host device is physically located at the physicallocation of the power distribution unit.

FIG. 2 is a schematic block diagram of an example simplified device 200that may be used with one or more embodiments described herein, e.g., asany of the devices shown in FIG. 1 above (e.g., host device 130 or PDU120). The device 200 may comprise one or more data network interfaces210 (e.g., Ethernet or other protocols, notably whether wired orwireless), at least one power connection/supply 220, and whateverfunctional circuitry 230 (e.g., a processor, memory, operating systems,software programs, data structures, etc.) the device 200 requires forits configured functionality. As described below, one such datastructure may be a management information base (MIB) 235.

The network interface(s) 210 contain the mechanical, electrical, andsignaling circuitry for communicating data over links coupled to thedata network 140. The network interfaces may be configured to transmitand/or receive data using a variety of different communicationprotocols. Also, in accordance with the techniques herein, a powerconnection/supply 220 is configured to allow for communicating throughthe powered connection 125, such as for power-line communication (PLC).

The processing circuitry (“ID module”) 240 may contain data structuresand/or computer executable instructions executed by a processor toperform functions as described herein. Illustratively, the techniquesdescribed herein may be performed by the processing circuitry 240 ashardware, software, and/or firmware, and may be performed in conjunctionwith functional circuitry 230. It will be apparent to those skilled inthe art that other processor and memory types, including variouscomputer-readable media, may be used to store and execute programinstructions pertaining to the techniques described herein. Also, whilethe description illustrates various processes or circuitry, it isexpressly contemplated that various processes may be embodied as modulesconfigured to operate in accordance with the techniques herein (e.g.,according to the functionality of a similar process). Further, while theprocesses/circuitry may have been shown separately, those skilled in theart will appreciate that processes may be routines or modules withinother processes.

In general, the techniques herein are based on communication between ahost device 130 (e.g., server, switch, storage device, computer, etc.)and a PDU 120. Host devices 130, in particular, may comprise processingcircuitry 240 that is located within the device (e.g., within thechassis), and that stores identification (ID) information for the hostdevice. That is, information about the device may be “built” into aframe (e.g., configured statically (e.g., flashed) into the processingcircuitry 240), and as described below, modulated and broadcast acrossthe power-line (e.g., at regular intervals) via the power supply orsupplies in the device. Such information may comprise, for example, oneor more of the following pieces of information about the host (e.g., andstored in a database of the processing circuitry):

-   -   Configured name;    -   Configured management IP address;    -   Manufacturer;    -   Device type/model;    -   Device serial number;    -   Number of rack units the device takes up;    -   Maximum possible power draw of the device;    -   Current power draw (a dynamic/adjusted value);    -   Etc.

According to one or more embodiments herein, a smart PDU 120 may besimilarly configured, where the PDU's processing circuitry (ID module)240 (e.g., a database of the processing circuitry) may be configuredwith (but not limited to):

-   -   Configured name;    -   Configured management IP address;    -   Manufacturer;    -   Device type/model;    -   Device serial number;    -   Rack/physical location;    -   Etc.        This PDU information may also be built into a frame, modulated        and broadcast across the power-line to the host device in        various configurations, as described below.

Illustratively, FIG. 3 is an example of device identification overpower-line for data center management, where two generic devices 200 areshown (e.g., one as a host device 130 and one as a PDU 120). In general,the connectivity over the powered connection 125 may be based ontransmitting data packets or frames 310, where such packets/frames 310may be exchanged among the devices 200 using predefined power-linecommunication protocols, where a protocol consists of a set of rulesdefining how the devices interact with each other. In general, there areseveral existing technologies that are able to provide datacommunication over power-lines, such as those that support Ethernet overpower (e.g., IEEE Std 1901-2010). In this particular example embodiment,Layer Discovery Protocol (LLDP—IEEE 802.1AB) frames may be used over thePLC links, where LLDP uses mandatory, optional, and organizationallyspecific Type-Length-Variable (TLV) fields to encode information totransmit. These TLVs can be utilized to send the identificationinformation fields described previously.

Information contained in packets exchanged between the devices 200 maybe stored in a Management Information Base (MIB) 235, which althoughshown in the functional circuitry 230 may alternatively (oradditionally) be stored within the processing circuitry (ID module) 240.The information collected by the devices may then be accessible via adata network 140 to a server 300 (e.g., separate servers 300 a and 300b, or else a same server), such as by using an application programminginterface (API), simple network management protocol (SNMP), or web basedsystem, so the information can be accessed by and/or collated in anexternal inventory database at the server(s) through associated datanetwork packets/frames 320.

FIGS. 4A-4C illustrate example options for communications for datacenter management using device identification over power-line inaccordance with one or more embodiments of the techniques herein. Inparticular, FIG. 4A illustrates an example where both the host device130 and PDU 120 share the information. For instance, the communicationlayer and host component (processing circuitry 240 of host device 130)illustratively activates as soon as a power connection is made betweenthe smart PDU 120 and the device 130. Once the power-line link layerconnection has been established the, host device 130 and PDU 120 mayboth send/receive frames 310 to/from each other, exchanging theidentifying information. (Note that as described below, the devices mayhave a timeout to expire entries when it receives no broadcast packetsfor a configurable period.) Once the information is exchanged over thepowered connection 125, each device (host device 130 and PDU 120) maythen relay that information over the data network 140 to a respective(or shared) server 300.

Conversely, as shown in FIG. 4B, an alternative embodiment requires onlythe PDU 120 to communicate the information over the data network 140 toa server 300. That is, the host device 130 may communicate itsidentification information over the power-line to the PDU 120, at whichtime the PDU may send this information, along with its own information,to an associated server 300. As still another alternative embodiment,FIG. 4C illustrates a situation where only the host device 130communicates the information over the data network 140 to a server 300.Here, the PDU 120 may communicate its identification information overthe power-line to the host device 130, at which time the host device maysend this information, along with its own information, to an associatedserver 300.

FIG. 5A illustrates an example simplified procedure 500 a for datacenter management using device identification over power-line inaccordance with one or more embodiments described herein, particularlyfrom the perspective of a host device 130 communicating itsidentification information (illustratively representing the situation inFIG. 4B above, but also portions of FIGS. 4A and 4C, accordingly). Theprocedure 500 a may start at step 502, notably storing itsidentification information locally, and continues to step 504, where, asdescribed in greater detail above, the host device 130 determines, overa power connection, that the device is in powered connectivity with thePDU 120 (i.e., is powered on). If so, then in step 506, the host device130 may send its identification information (ID info) over the powerconnection to the PDU 120. Said differently, the host device 130communicates with the PDU 120 over the power connection (in response tothe powered connectivity), and exchanges its identification informationwith the PDU, such that the communicated identification information isaccessible to another device (e.g., service 300) via a data network 140due to the communicating over the power connection, as described herein.So long as the power is not down in step 508, then the communicatedinformation may be refreshed in step 506, and procedure 500 a continuesaccordingly.

FIG. 5B, on the other hand, illustrates an example simplified procedure500 b for data center management using device identification overpower-line in accordance with one or more embodiments described herein,particularly from the perspective of either a host device 130 or PDU 120communicating received identification information (illustrativelyrepresenting any of the situations in FIGS. 4A-4C above). The procedure500 b may start at step 522, and continues to step 524, where, asdescribed in greater detail above, the device 200 (host device 130 orPDU 120) determines, over a power connection, when the device is inpowered connectivity with the other device, and is receiving informationover that powered connection. For instance, as described above in FIG.5A, the host device may determine powered connectivity based on beingpowered on. However, the PDU 120 may determine powered connectivitybased on receiving a communication at the PDU from the host device overthe power connection. (Other techniques for detecting connectivity mayalso be used, and those mentioned herein are not meant to be limiting.)The information in step 524 may generally consist of identificationinformation of at least one of either the host device 130 or PDU 120.

Assuming there is no timeout event in step 526, and in response to anactual change to the information in step 528 (for example, the firstlearned instance, or else other changes, such as dynamic information,e.g., current power utilization), the local MIB 235 may be updated instep 530, accordingly. Note that in response to a timeout in step 526,the MIB may also be updated (e.g., noting the timeout or removing theentry) in step 530. This learned information (i.e., the identificationinformation of the connected device and of the local device) may then besent to another device (e.g., server) over the data network 140 in step532. For instance, as described above, step 532 may be in response tospecific polling from the server 300, or else may be uploaded/updated asnew information becomes available, or else periodically to avoid atimeout at the servers. (Note that as described below, the PDU 120 mayalso communicate power management messages regarding the host devicewith a power management system/server 300 over the data network, andcommunicates/relays those messages with the host device over the poweredconnection.)

According to the techniques herein, therefore, since the PDU 120 isassociated with a physical location, and the communicated identificationinformation accessible via the data network (e.g., to server 300)includes the associated physical location, the host devices 130 may belocated/inventoried by a server 300 or other management device oraccessing process/application.

FIG. 5C illustrates an example simplified procedure 500 c for datacenter management using device identification over power-line inaccordance with one or more embodiments described herein, particularlyfrom the perspective of a management device (e.g., server 300). Theprocedure 500 c may start at step 542, and continues to step 544, where,optionally, the management device may poll or otherwise request theinformation described above, and may receive the information (asrequested or else as received without a specific request) in step 546.Said differently, a server 300 may receive, over a data network,identification information of a host device 130 and a PDU 120, where thehost device and PDU initially communicated the identificationinformation over a power connection 125 that provides poweredconnectivity from the PDU to the host device, as described in detailabove. In particular, as described above, since the PDU 120 isassociated with a physical location, in step 548 the management devicemay locate the devices by determining, based on the identificationinformation, a physical location of the PDU, and then deducing, based onthe physical location of the PDU, that the host device 130 is physicallylocated at the physical location of the power distribution unit. Havingthis information available grants the management device variousbenefits, such as inventory, confirmation (e.g., the ability to rapidlyidentify serial numbers of devices to link against support contracts),and other diagnosis/management functionalities.

For instance, optionally, in step 550, various levels of diagnosing maytake place at the management device (e.g., server 300), such asdetermining, based on the identification information, adual-power-supply issue with the host device 130. For instance, thedual-power-supply issue may be based on whether the host device is inproper powered connectivity with two different PDUs, such as only havingone PDU supplying power to both power supplies of the host device, onlyhaving power to one PDU where another power supply has no power, etc.There is also the possibility for the management device to collect andreport on power oversubscription based on current power utilization.

Notably, dual-power-supply issues may also be power-grid based, wherethe redundant PDUs are not merely supplying two options for receptacles,but where each of the redundant PDUs is on a different powersource/grid. In this manner, determining a dual-power issue may resultin detecting which servers are connected with a single power sourceversus also properly having a backup power source, such as by comparingthe associated PDUs to knowledge of which grid source each PDU isconnected to. If the two PDUs are improperly sourced by the same powergrid, a notification may be generated to indicate that the associateddevice is only backed by single power source instead of two distinctpower sources (e.g., in the case where a default policy requires orrecommends two sources).

Further, and as described in greater detail below, in step 552 themanagement device may optionally perform power management functions,such as communicating power management messages regarding the hostdevice with the PDU over the data network, where the PDU communicatesthe messages with the host device over the powered connection (or elsesimply acts on the power management message, such as turning off powerto the host device).

Note also that power management functions may comprise planned outages,where action may entail notifying device administrators ahead of time,and optionally raising an alert if a device is backed by a single powersource that is going to go down.

In still another embodiment, a physical host device may be hostingmultiple virtual machines (VMs). Based on the power state (single/dual),and optionally also based on the service level agreement (SLA) for theVMs running on these host devices, power management may comprise movingthe VMs to another host device in the data center, or perhaps notifyingthe VM owners about the planned outage. (Note that in the case of acloud/hosted environment, the VM owner is typically unaware of thephysical server—in that case, the system may simply automatically movethat VM to meet the SLA (uptime/availability/etc.).) This particularembodiment may be used to support programmable data centers—withauto-migration policies that include the power source as an additionalvariable, e.g., in addition to the load on the server, traffic patterns,and other factors.

As such, the power management functions of step 552 may generallycomprise determining that there is a planned power outage within a datacenter (e.g., in which a given host device and PDU reside), anddetermining, based on the identification information (e.g., powersupply/grid, VM allocation, policies, SLAs, etc.), whether any advancedpower-based action is to be performed within the data center in responseto the planned power outage (e.g., notifications, migrations, etc.). Assuch, the power is management function would then also compriseperforming the advanced power-based action by the server, accordingly.

The simplified example procedure 500 c may then end in step 554, thoughnotably the procedure 500 c may continue to operate to receive updatedinformation, perform further polls/queries, administer various powermanagement functions or diagnoses, and so on.

By building the host identification component (ID module 240) into ahost device 130, host identification can now be tied to a given chassis,no matter where it is placed in a data center, providing the ability toeasily and automatically establish a host-to-location linkage. FIGS.6A-6D illustrate examples of data center management using deviceidentification over power-line in this manner, where FIG. 6A illustratesan example data center 600 with a plurality of racks 110 and associateddual PDUs 120 (120 a and 120 b). As shown, each of the PDUs 120 withinthe data center 600 is identified with a number from “1” to “18”, andthe assumption herein is that each of the physical locations of PDUs “1”to “18” is known/configured on the corresponding PDUs. As a particularhost device 130 a is plugged into both PDUs “1” and “2”, it can bedetermined that the device 130 a is located at the physical location(rack 110) of PDUs “1” and “2”.

As shown in FIG. 6B, as the host device 130 a is moved from one locationto another and plugged in, such as to PDUs “11” and “12”, the system isupdated with the new physical location based on the new exchange betweenhost device 130 a and PDUs “11” and “12” being picked up by the externalinventory database (server 300) on the next polling run across the datacenter and/or host devices as described above. As such, the only manualmodification is the lifting and shifting of the hardware, and pluggingit into the PDU at its new location, saving time and increasing theaccuracy of inventories as this part of the process is carried out bythe machine itself.

Since PDUs will generally be deployed in a known location, and PDUs willbe configured as part of a data center deployment and left static duringthe operational phase of a data center, devices that are (as they shouldbe) connected to PDUs in the rack they reside may be automatically tiedto an associated physical location. The techniques herein, therefore,give data centers the ability to perform self inventories that are keptup-to-date as equipment moves within, in, out or between facilities.Note that this technology also has applications outside of data centerfacilities, such as anywhere that has hosts that can be spread across alarge area, such as a campus, manufacturing or conference facilities. Italso allows data center administrators to identify what PDU a piece ofequipment is plugged into so that remote power off/on is easier, asdescribed below.

In addition to inventory management, the techniques herein also allowfor various diagnosis mechanisms, such as by querying A-side and B-sidesmart PDUs in a rack to provide rapid highlighting of devices withsingle or failed power supplies during data center power maintenance.For example, as shown in FIG. 6C, it can be determined that host device130 a may be suffering from a power supply failure or a removed powercord if there is only one PDU (“2”) receiving the power-connection-basedidentification information (e.g., and assuming it is known that device130 a should have two power supplies). Alternatively, as shown in FIG.6D, it can be determined that both power supplies of the host device 130a are improperly plugged into the same PDU “1”, which can causeadministrator alarms or other remedial actions.

In accordance with one or more additional or alternative embodimentsherein, the techniques may also be used in conjunction with off-bandpower management networks, which may generally be used to control PDUsover data networks, where the PDU receives power management commands topowercycle the attached devices. Supplying the location informationherein, particularly the ability to dynamically track this information,is crucial for operation of such power management (e.g., assuming thespecific power port/plug/receptacle is also identifiable). Additionally,however, the techniques herein may be used to extend the powermanagement ability of this power management network. For example, inthis particular extended embodiment, the PDU would provide access to thepower management network over the data network 140, and the PDU itselfcan act as a switching device which carries frames (e.g., Ethernetframes) over the last hop to the device endpoints over the power-lineconnection.

FIG. 7 illustrates an example communication for data center managementusing device identification over power-line in accordance with thisparticular embodiment, where the server 300 communicates a managementcommand/request over the data network 140 to the PDU 120. The PDU maythen communicate the management over the powered communication link 125to the corresponding host device 130. Note that optionally, the returncommunications (e.g., status, replies, etc.) may be relayed back tothrough the PDU over the same communication mediums (e.g.,PLC-to-Ethernet), accordingly.

FIG. 8A illustrates an example schematic block diagram of a system inaccordance with this embodiment for data center management overpower-line, where the PDU 120 is shown with switching circuitry 810,which is configured to switch (or route or forward) communications froma power management data network 140 onto the powered connections 220 a-cover power-lines to devices 130 a-c, respectively. (Notably, thisoperation may require a protocol conversion between the data network andPLC connections at the switching circuitry 810.) Based on an addressingscheme, the power management servers 300 may be able to communicate withthe power management components/circuitry of the host devices 130through the PDUs 120. That is, by associating the identification of ahost device 130 along with the specific location of a PDU 120, remotepower management of the devices can be achieved through unifying theoff-band access to the server right from the PDU/power managementinfrastructure—minimize cabling and clutter, broadening access, etc. Forinstance, as shown in FIG. 8B, management messages from the powermanagement data network can be communicated (e.g., forwarded) to theappropriate host device (e.g., host device 130 c), or else as shown inFIG. 8C, the PDU can simply act on the management command, such asshutting down the associated power connection 220 c.

FIG. 9 illustrates an example simplified procedure 900 for data centermanagement using device identification over power-line in accordancewith this extended embodiment, particularly from the perspective of aPDU 120 communicating management commands. The procedure 900 may startat step 902, and continues to step 904, where, as described in greaterdetail above, a management command is received on the data network 140at the PDU 120 (i.e., communicating power management messages regardingthe host device). If the command is for the PDU act in step 906, thenthe PDU acts accordingly in step 908, such as shutting down a powersupply, returning power utilization reports, etc. Conversely, in step910 the PDU may forward the command on the powered connection 125 (thatis, communicates the power management messages with the host device overthe powered connection), as mentioned above. Optionally, in step 912,the PDU may receive a reply on the power connection 125, and may forwardthat reply on the data network 140 back to the power management server300, accordingly, in step 914 (i.e., communicating power managementmessages over the powered connection and data network, respectively).The illustrative and simplified procedure 900 may then end in step 916,notably with the option to continue communicating power managementmessages as necessary.

It should be noted that while certain steps within procedures 500 a-cand 900 may be optional as described above, the steps shown in FIGS.5A-5C and FIG. 9 are merely examples for illustration, and certain othersteps may be included or excluded as desired. Further, while aparticular order of the steps is shown, this ordering is merelyillustrative, and any suitable arrangement of the steps may be utilizedwithout departing from the scope of the embodiments herein. Moreover,while procedures 500 a-c and 900 are described separately, certain stepsfrom each procedure may be incorporated into each other procedure, andthe procedures are not meant to be mutually exclusive.

The techniques described herein, therefore, provide for data centermanagement using device identification over power-line. In particular,the techniques herein provide a mechanism for PDUs (power strips) in adata center rack to help identify what devices are in the associatedrack, by communicating over the powered connection, and throughcommunication of the device inventory upstream to a management solution.This marriage of systems enables a greater intersection of data pointsfor analytics, and provides various benefits that come from having anaccurate inventory of devices and their locations. For instance, withthe techniques herein, a device only needs to be plugged in to power tobe audited, allowing for rapid identification of location and quantityof hardware within a data center, and to quickly determine the powerstate of such devices (e.g., an improper configuration, power supplyfailure, power oversubscription, etc.).

While there have been shown and described illustrative embodiments thatprovide for data center management using device identification overpower-line, it is to be understood that various other adaptations andmodifications may be made within the spirit and scope of the embodimentsherein. For example, the embodiments have been shown and describedherein with relation to data centers and associated networks and/orconnectivity. However, the embodiments in their broader sense are not aslimited, and may, in fact, be used with other types of devices, networkconfigurations, and so on (and particularly need not be associated withdata centers). In addition, while certain protocols are shown, such aspower-line communication protocols and/or discovery protocols, othersuitable protocols may be used, accordingly.

The foregoing description has been directed to specific embodiments. Itwill be apparent, however, that other variations and modifications maybe made to the described embodiments, with the attainment of some or allof their advantages. For instance, it is expressly contemplated thatcertain components and/or elements described herein can be implementedas software being stored on a tangible (non-transitory)computer-readable medium (e.g., disks/CDs/RAM/EEPROM/etc.) havingprogram instructions executing on a computer, hardware, firmware, or acombination thereof. Accordingly this description is to be taken only byway of example and not to otherwise limit the scope of the embodimentsherein. Therefore, it is the object of the appended claims to cover allsuch variations and modifications as come within the true spirit andscope of the embodiments herein.

What is claimed is:
 1. A method, comprising: storing, on a first device,identification information of the first device, wherein the first deviceis a power distribution unit; determining, over a power connection, whenthe first device is in powered connectivity with a second device,wherein the second device is a host device; communicating, with thesecond device over the power connection in response to the poweredconnectivity, identification information of at least one of either thefirst device or the second device; communicating, by the powerdistribution unit with a power management system over a data network,power management messages regarding the host device; and communicating,by the power distribution unit with the host device over the poweredconnection, the communicated power management messages, wherein thecommunicated identification information is accessible to a third devicevia the data network due to the communicating over the power connection.2. The method as in claim 1, wherein the power distribution unit isassociated with a physical location, and wherein the communicatedidentification information accessible to the third device via the datanetwork includes the associated physical location.
 3. The method as inclaim 1, wherein communicating comprises: sending the identificationinformation of the first device to the second device, wherein the seconddevice is configured to send the identification information of the firstdevice and identification information of the second device to the thirddevice over the data network.
 4. The method as in claim 1, whereincommunicating comprises: receiving identification information of thesecond device at the first device; wherein the method further comprises:sending the identification information of the first device and theidentification information of the second device to the third device overthe data network.
 5. The method as in claim 1, wherein determining whenthe first device is in powered connectivity with the second devicecomprises: receiving a communication at the power distribution unit fromthe host device over the power connection.
 6. The method as in claim 1,further comprising: refreshing the communicating, with the second deviceover the power connection, the identification information of at leastone of either the first device or the second device.
 7. An apparatus,comprising: at least one network interface configured to communicate ona data network; at least one power connection configured to engage inpower connectivity with a second device and to communicate with thesecond device, wherein the second device is a host device; a processingcircuit coupled to the network interface and power connection, andconfigured to execute a process, the process when executed configuredto: store identification information of the apparatus, wherein theapparatus is a power distribution unit; determine, over the powerconnection, when the apparatus is in powered connectivity with thesecond device; communicate, with the second device over the powerconnection in response to the powered connectivity, identificationinformation of at least one of either the apparatus or the seconddevice; communicate, with a power management system over the datanetwork, power management messages regarding the host device; andcommunicate, with the host device over the powered connection, thecommunicated power management messages, wherein the communicatedidentification information is accessible to a third device via the datanetwork due to the communicating over the power connection.
 8. Theapparatus as in claim 7, wherein the power distribution unit isassociated with a physical location, and wherein the communicatedidentification information accessible to the third device via the datanetwork includes the associated physical location.
 9. The apparatus asin claim 7, wherein the process when executed to communicate is furtherconfigured to: send the identification information of the apparatus tothe second device, wherein the second device is configured to send theidentification information of the apparatus and identificationinformation of the second device to the third device over the datanetwork.
 10. The apparatus as in claim 7, wherein the process whenexecuted to communicate is further configured to: receive identificationinformation of the second device at the apparatus; wherein the processwhen executed is further configured to: send the identificationinformation of the apparatus and the identification information of thesecond device to the third device over the data network.
 11. A method,comprising: receiving, by a server over a data network, identificationinformation of a host device and a power distribution unit, wherein thehost device and the power distribution unit initially communicated theidentification information of the host device and the power distributionunit over a power connection that provides powered connectivity from thepower distribution unit to the host device; determining, by the serverbased on the identification information of the host device and the powerdistribution unit, a physical location of the power distribution unit;deducing, by the server based on the physical location of the powerdistribution unit, that the host device is physically located at thephysical location of the power distribution unit; and communicating, bythe server with the power distribution unit over the data network, powermanagement messages regarding the host device, wherein the powerdistribution unit communicates the power management messages with thehost device over the powered connection.
 12. The method as in claim 11,further comprising: determining, by the server based on theidentification information of the host device and the power distributionunit, a dual-power-supply issue with the host device, thedual-power-supply issue based on whether the host device is in properpowered connectivity with two different power distribution units. 13.The method as in claim 11, further comprising: determining, by theserver, that there is a planned power outage within a data center inwhich the host device and power distribution unit reside; determining,by the server based on the identification information of the host deviceand the power distribution unit, whether any advanced power-based actionis to be performed within the data center in response to the plannedpower outage; and if so, performing the advanced power-based action bythe server.